Negative-ELISA using native and filtrated cystic fluid antigens to rule out cystic echinococcosis
Issued Date
2004
Resource Type
Language
eng
Suggested Citation
Paron Dekumyoy, พารณ ดีคำย้อย, Doungrat Riyong, Wallop Pakdee, วัลลภ ภักดี, Jitra Waikagul, จิตรา ไวคกุล (2004). Negative-ELISA using native and filtrated cystic fluid antigens to rule out cystic echinococcosis. Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/63401
Title
Negative-ELISA using native and filtrated cystic fluid antigens to rule out cystic echinococcosis
Other Contributor(s)
Abstract
An increasing number of cases of echinococcosis in Thailand have been imported, probably native infections and medical transfers. Serodiagnosis is one diagnostic choice for interpreting infections before a further step is done. Due to limited antigen, indirect ELISA has been used as a negative screening test for IgG-detection to rule out echinococcosis. Native hydatid cystic fluid (HCF) antigen from Belgium was used for such testing, in which the ODs-ELISA of samples were compared with those of two positive controls. Subsequently, hydatid cyst fluid from a Thai patient was obtained and the filtrated cyst fluid antigen [(30)-(10) kDa, HCF30.10] was prepared to develop negative screening results for the serum samples. By using HCF, three of twenty-four samples resulted in higher ODs-ELISA than the controls. In an attempt to observe the cross-reactivity of this native antigen, IgG-antibodies from many helminthiases cross-reacted and showed high ODs-ELISA. The HCF30.10 Ag was used to develop the test and analyze IgG-antibodies from 5 positive controls (2 parasite-confirmed and 3 positive-serodiagnosed), 183 heterologous cases of 29 diseases and 50 healthy control sera. At a cut-off value of 0.484, the test had 100% sensitivity and 42% specificity. Only Malayan filariasis, onchocercosis, fascioliasis, amebiasis, giardiasis and blastocystosis gave true negatives. Antibodies from nematodiases strongly cross-reacted with HCF30.10 Ag. Nine of fifty (18%) healthy serum controls produced higher OD-values than the cut-off. The routine ELISA uses the HCF30.10 Ag to produce a negative result to echinococcosis, because limited cystic fluid antigen (Thai patient) for test improvement, a lot of cross-reactions and only two protoscolex-positive controls are available.
Description
Joint International Tropical Medicine Meeting 2004: Ambassador Hotel, Thailand 29 November-1 December 2004: abstract. Bangkok: Faculty of Tropical Medicine, Mahidol University; 2004. p.195.